1925] Setchell-Gardner : Melaiiophyceae 417 



however, have a glistening appearance, as though they were abortive 

 or in a pathological condition, while those represented by Sauvageau 

 are producing zoospores. This condition in which we find ours is 

 quite common among our Pacific Coast species of Ectocarpus. We 

 have not yet seen a single specimen in which the so-called seriate 

 zoosporangia show any indication of producing zoospores. 



4. Ectocarpus tomentosus (Huds.) Lyngb. 



Fronds tufted or caespitose, consisting of masses of erect, simple 

 or branched, rope-like strands, yellowish brown to dark brown ; pros- 

 trate filaments short, irregularly branched ; erect filaments twisted 

 together into rope-like masses, 1 mm. to 20 cm. high ; main branches 

 long, divergent ; ultimate ramuli profuse, alternate, irregularly spaced, 

 never opposite, mostly short and patent, subpiliferous, often hooked 

 at the tips; cells of the main erect filaments 8-12^ broad, 1.5-2.5 times 

 as long as broad, especially below, mostlj^ quadrate above ; ehromato- 

 phores irregularly band-shaped, few in each cell ; zoosporangia ovoid, 

 terminal or lateral, 28-36,/x long, 20-26|U, broad ; gametangia lateral, 

 patent, often secund, straight or recurved, sessile or on short pedicels, 

 25-75ju, long, 10-15/a broad. 



Growing on members of the Fucaceae. Extending from Alaska 

 (Harvester and Kadiak Islands) to southern California (Laguna). 



Lyngbye, Hydrophyt. Dan., 1819, p. 132, pi. 44A 1-3; Greville, 

 Crypt. Flor., vol. 6, 1828, pi. 316; Saunders, Phyc. Mem., 1898, p. 155, 

 pi. 24, figs. 1, 2, Alg. Harriman Exp., 1901, p. 417; Setchell and 

 Gardner, Alg. N.W. Amer., 1903, p. 238. Ectocarpus tame^itosoides 

 Guernsey, Notes on Mar. Alg., 1912, p. 198. Conferva fomentosa 

 Hudson, Fl. Angl., 1762, p. 480 (in part). (Ed. 2, 1778, p. 594.) 



Our idea of Ectocarpus tomentosus dates back definitely only to 

 Dillwj^n. His interpretation difiPers somewhat from that of botanists 

 earlier than his time, but is probably as reliable an interpretation of 

 the species of Hudson as may be possible. Much hinges on the ideas 

 as to the identity of the plant of Dillenius (1741, p. 19, pi. 3, fig. 19) 

 figured and described under the name of Conferva marine, tomentosa, 

 minus tenera et ferruginea which is quoted by Hudson among the 

 synonyms of his species. The figure of Dillenius is not reassuring 

 and Dawson Turner (Trans. Linn. Soc, vol. 7, 1804, p. 105), as 

 quoted by Dillwyn, states that the specimen in the Dillenian Her- 

 barium "is only a bad specimen of C. littoraU^." Dillwyn. however. 



